In general, a refrigerator is an apparatus that discharges cool air generated by a refrigerating cycle involving a compressor, a condenser, an expansion valve, and an evaporator to lower the temperature in the refrigerator such that food is stored in a frozen state or in a refrigerated state.
A refrigerator generally includes a freezing compartment for storing food or beverages in a frozen state and a refrigerating compartment for storing food or beverages in a refrigerated state.
Refrigerators are classified into a top mount type refrigerator, in which a freezing compartment is disposed above a refrigerating compartment, a bottom freezer type refrigerator, in which a freezing compartment is disposed under a refrigerating compartment, or a side by side type refrigerator, in which a freezing compartment and a refrigerating compartment are disposed side by side. In all cases, doors are provided at the freezing compartment and the refrigerating compartment such that access to the freezing compartment and the refrigerating compartment is possible through the doors.
In addition to refrigerators in which a freezing compartment and a refrigerating compartment are partitioned from each other, there are also refrigerators in which access to a freezing compartment and a refrigerating compartment is possible through a single door. Most such single door type refrigerators are small-sized, and the freezing compartment is generally provided in a specific space inside the refrigerating compartment.
In addition, there is a French type refrigerator, in which an upper refrigerating compartment is opened and closed by left and right doors, as a kind of top mount type refrigerator. A freezing compartment of the French type refrigerator may also be opened and closed by left and right doors.
In recent years, the functions of the refrigerator have been diversified in addition to the original functions of the refrigerator, including storage of food in a frozen state or in a refrigerated state. For example, a dispenser may be mounted in the door of the refrigerator to provide clean water and ice, or a display unit may be mounted to the front of the door to display the state of the refrigerator such that the refrigerator can be appropriately controlled.
In general, the door of the refrigerator, which is provided to open and close the storage compartment, is opaque. That is, the door is provided as a heat insulation wall that defines the refrigerating compartment and the freezing compartment. However, the door is a heat insulation wall that can be opened and closed so that a user can access the refrigerating compartment or the freezing compartment. For this reason, it is not possible for the user to check the kinds and positions of goods stored in the storage compartment before the user opens the door.
The largest amount of cool air is lost when the door is opened. As the amount of time for which the door is open is increased, energy loss is further increased.
In general, various kinds of goods are stored in the refrigerating compartment or the freezing compartment. Consequently, it takes a predetermined amount of time for the user to find a desired item and take it out. That is, the user looks around the storage compartment to find a desired item in the state in which the door is open, which takes a considerable amount of time.
Such unique characteristics of the refrigerator cause user inconvenience and increase energy consumption.
In recent years, a refrigerator configured such that a portion of the storage compartment is openable has been proposed. That is, a refrigerator having a sub door for opening and closing a sub storage compartment provided in a main door has been proposed. The sub storage compartment is a portion of a main storage compartment. At least a portion of the sub storage compartment may be partitioned from the main storage compartment by a partition wall. The sub storage compartment may be provided in front of the main storage compartment. This type of refrigerator may be called a door in door (DID) refrigerator. When the sub door is opened, the leakage of cool air from the main storage compartment is somewhat reduced, thereby achieving an energy saving effect.
In the DID refrigerator, the user may open the main door to access the main storage compartment. The reason for this is that when the main door is rotated open, the sub storage compartment is also rotated together with the sub door.
For example, goods that are frequently used, such as beverages, may be stored in the sub storage compartment. The sub door may be opened, without opening the main door, in order to access the sub storage compartment.
Meanwhile, there is also a home-bar refrigerator having a home-bar door. A home bar may be a very small sub storage compartment. That is, the home-bar door, which is mounted in a portion of the main door, may be opened to store a small number of beverages in the home bar, which is provided in the rear of the main door.
A refrigerator having an enlarged home-bar may be considered a DID refrigerator.
In the DID refrigerator and the home-bar refrigerator, however, problems may be caused as the volume of the sub storage compartment is increased and the number of goods stored in the sub storage compartment is increased. That is, it takes a predetermined amount of time for the user to open the sub door or the home-bar door and to find a desired item and take it out, which causes user inconvenience and increases energy consumption.